FAQ – How can it be that these natural enemies only attack one plant?

Most fungal and insect species are restricted in what they are able to infect or feed on, and some are monophagous, meaning they will only attack one species of plant. This is not as surprising as it seems. Many endangered insects are under threat because their only host plant or its habitat has become rare and they are unable to feed on anything else. Of course some insect and fungal species will feed or infect a wide range of plant species but these are rejected as potential natural control agents early in the safety testing regime.